U.S. patent number 6,978,882 [Application Number 10/709,614] was granted by the patent office on 2005-12-27 for device for automated manipulation of articles.
This patent grant is currently assigned to imt robot AG. Invention is credited to Peter Nagler.
United States Patent |
6,978,882 |
Nagler |
December 27, 2005 |
Device for automated manipulation of articles
Abstract
A device for automated manipulation of articles along a
predetermined movement path has a working area having a working
surface for articles. The device also has a manipulator with a
gripping device for moving the articles. The working surface
consists of neighboring longitudinal elements, wherein longitudinal
gaps are formed between the neighboring longitudinal elements. The
griping device has at least one gripping finger that can be lowered
into the longitudinal gaps between the neighboring longitudinal
elements and moved into a position underneath an article for
picking up the article. The article is essentially secured in the
gripping device by a combination of acceleration forces generated
along a movement path of the gripping device and of the force of
gravity.
Inventors: |
Nagler; Peter (Fellbach,
DE) |
Assignee: |
imt robot AG (Fellbach,
DE)
|
Family
ID: |
33155148 |
Appl.
No.: |
10/709,614 |
Filed: |
May 18, 2004 |
Foreign Application Priority Data
|
|
|
|
|
Jun 4, 2003 [EP] |
|
|
03012642 |
|
Current U.S.
Class: |
198/750.11;
198/468.2 |
Current CPC
Class: |
B25J
9/0093 (20130101); B25J 15/00 (20130101); B65G
47/52 (20130101); B25J 11/0045 (20130101); B65G
2207/26 (20130101); B65G 2207/38 (20130101) |
Current International
Class: |
B65G 025/04 () |
Field of
Search: |
;198/690.2,692,693,468.2,698,699,699.1,750.11 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
20203818 |
|
May 2002 |
|
DE |
|
2 725 430 |
|
Apr 1996 |
|
FR |
|
04 039214 |
|
Feb 1992 |
|
JP |
|
06 219548 |
|
Aug 1994 |
|
JP |
|
07 132477 |
|
May 1995 |
|
JP |
|
Primary Examiner: Bidwell; James R.
Attorney, Agent or Firm: Huckett; Gudrun E.
Claims
What is claimed is:
1. A device for automated manipulation of articles along a
predetermined movement path, the device comprising: a working area
having a working surface for articles; a manipulator arranged in
the working area and comprising a pick-up device for moving the
articles; wherein the working surface is comprised of neighboring
longitudinal elements, wherein longitudinal gaps are formed between
the neighboring longitudinal elements; wherein the pick-up device
has at least one pick-up finger configured to be lowered into the
longitudinal gaps between the neighboring longitudinal elements and
to move into a position underneath an article for picking up the
article; wherein the article is essentially secured in the pick-up
device by a combination of acceleration forces generated along a
movement path of the pick-up device and of the force of
gravity.
2. The device according to claim 1, wherein the article is released
from the at least one pick-up finger by accelerations of the
pick-up device in the direction of the acceleration due to gravity
and is placed onto a predetermined target location by prompt
retraction of the pick-up device from the article.
3. The device according to claim 2, wherein the acceleration of the
pick-up device is greater than the acceleration due to gravity.
4. The device according to claim 1, wherein the pick-up device is
comprised exclusively of components arranged rigidly and immobile
relative to one another.
5. The device according to claim 1, wherein the pick-up device has
a pivot axis extending approximately parallel to the working
surface and is configured to tilt about the pivot axis.
6. The device according to claim 1, wherein the pick-up device is
U-shaped comprising a stay and a first and a second legs connected
to ends of the stay, wherein the stay determines a receiving width
of the pick-up device for the article, wherein the first leg is
formed by the pick-up finger, wherein the second leg is a fastening
leg configured to connect the pick-up device to a manipulator arm,
and wherein a connecting area where the fastening leg and the
manipulator arm are connected is positioned above a center of
gravity of the pick-up device.
7. The device according to claim 1, wherein the pick-up device has
a lateral support flange for closing at least partially a lateral
surface of the pick-up device, wherein the support flange is
preferably shorter than the at least one pick-up finger.
8. The device according to claim 7, wherein the lateral support
flange is positioned at least at one of a lateral spacing and a
horizontal spacing relative to the at least one pick-up finger
neighboring the lateral support flange.
9. The device according to claim 1, wherein the working surface is
comprised at least partially of a strap belt.
10. The device according to claim 1, wherein the working surface is
a conveyor belt and the articles to be manipulated are transported
on the conveyor belt into the working area of the pick-up
device.
11. The device according to claim 10, wherein the longitudinal
elements are connected to the conveyor belt such that the
longitudinal elements and the longitudinal gaps are aligned
transversely to a transport direction of the conveyor belt, wherein
the pick-up device for picking up the article moves transversely to
the transport direction of the conveyor belt into the position
underneath the article.
12. The device according to claim 11, wherein the pick-up device
for picking up the article is moved at the same time in the
transport direction of the conveyor belt.
13. The device according to claim 10, further comprising an
intermediate support onto which the article is lifted.
14. The device according to claim 13, further comprising a lifting
device for lifting the article, wherein the lifting device is
arranged underneath the working surface and is configured to pass
upwardly through the longitudinal gaps between the longitudinal
elements forming the conveyor belt.
15. The device according to claim 13, wherein the intermediate
support is positioned above the working surface.
Description
BACKGROUND OF INVENTION
1. Field of the Invention
The invention relates to a device for automated manipulation of
articles such as meat, fish, poultry or the like along a
predetermined movement path. The device is comprised of a working
surface for the articles provided in a working area as well as a
manipulator arranged within the working area and comprising a
gripping device for the articles to be moved, wherein the working
surface is comprised of longitudinal elements with longitudinal
gaps formed between neighboring longitudinal elements. The gripping
device has gripping fingers that can be lowered into the
longitudinal gaps between neighboring longitudinal elements of the
working surface and can be moved into a position underneath the
article for picking up the article.
2. Description of the Related Art
With such devices, articles such as meat, fish, poultry or the like
are moved by manipulators such as robots from a first position, for
example, on a belt, into a second position, for example, on another
belt. For example, cutlets can be lifted off a belt and placed into
a retail receptacle on a second belt or a fixed placement
position.
Since raw meat, fish, and poultry excrete liquids, there are
significant hygienic concerns in connection with using generally
known vacuum gripping device. Moreover, such vacuum gripping
devices leave contact traces on the articles that may negatively
affect the aesthetic appearance of the article.
SUMMARY OF INVENTION
It is an object of the present invention to provide a device for
automated manipulation of articles with which high hygienic
requirements are to be fulfilled.
In accordance with the present invention, this is achieved in that
the article essentially is secured in the gripping device by
acceleration forces generated along the movement path of the
gripping device in combination with the force of gravity.
By configuring the working surface so as to be comprised of
longitudinal elements with interposed longitudinal gaps, the
articles are resting on a grid or the like so that the gripping
device with a gripping finger can move into the longitudinal gap
and move into a position underneath the article. By lifting the
gripping device, the article is lifted off the working surface and,
along the further movement path to the target location, is safely
secured within the gripping device exclusively by the generated
acceleration forces in combination with the force of gravity. For
placing the articles, the acceleration forces are also used in that
the article is released from the gripping fingers by accelerating
the gripping device and is deposited by retracting the gripping
device. The actions of holding and placing of the article can be
enhanced by positioning the center of gravity of the article
between an axis of rotation and a rear wall of the gripping device.
In this way, the gripping device can be comprised of primarily
immobile components that are arranged rigidly on the gripping
device so that the gripping device itself has neither joints,
adjusting elements nor gaps for allowing movement between parts
into which the meat juice or similar liquids could penetrate. The
gripping device, comprised exclusively of immobile components,
fulfills also highest hygiene requirements and can be cleaned
simply and quickly. For example, by means of a simple shower the
gripping device can be kept clean even during extended operating
periods.
In order to ensure gripping or pick-up also under unfavorable
boundary conditions, as in the case of articles positioned closely
adjacent to one another, the gripping device can be tilted about a
pivot axis that is approximately parallel to the working surface so
that an article can be picked up by the gripping devices by a
movement similar to that of using a shovel.
Expediently, the lateral surfaces of the gripping device are at
least partially closed by lateral support flanges in order to
ensure even for great lateral accelerations a safe securing action
of the article in the gripping device. In this way, even quick
rotational movements about the vertical axis of the manipulator arm
can be carried out.
Preferably, the working surface is formed by a strap belt that
transports the articles within the working area of the
manipulator.
In a further embodiment of the invention, the longitudinal elements
and the longitudinal gaps between the longitudinal elements are
aligned transversely to the transport direction of the conveyor
belt wherein the gripping device for receiving the article moves
transversely to the transport direction of the conveyor belt into a
position underneath the article. This has the advantage that the
free space required for inserting the gripping device on the belt
is greatly reduced so that the articles can be placed closer
together in this way. Lowering of the gripping device to the level
of the belt can be initiated adjacent to the belt in order to then
move the gripping device, when entering the longitudinal gaps that
extend transversely to the transport direction of the belt,
simultaneously in the transport direction of the conveyor belt for
picking up the article.
According to another embodiment of the invention, the article can
be lifted onto an intermediate support. This is carried out
advantageously by a lifting device that is arranged underneath the
working surface and is configured to pass between the stays
upwardly. The intermediate support is advantageously provided above
the working surface.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a plan view onto the device according to the
invention.
FIG. 2 is a detail plan view onto a gripping device according to
the invention.
FIG. 3 is a side view of the gripping device of FIG. 2.
FIG. 4 is a plan view onto a device according to the invention
having longitudinal stays extending transversely to the transport
direction of the belt.
FIG. 5 is a side view of the belt according to FIG. 4
FIG. 6 is a side view of a device according to the invention
including an intermediate support.
FIG. 7 is a plan view onto the device according to FIG. 6 with a
gripping device lifting an article off the intermediate
support.
DETAILED DESCRIPTION
The device illustrated in FIG. 1 serves for automated manipulation
of articles, for example, pieces of meat (in the form of slices of
meat or the like), fish (for example, in the form of filets),
poultry (for example, as portioned parts), or similar food
articles. The illustrated working area 1 has a working surface 2
for the articles 3 that in the illustrated embodiment are slices of
meat (cutlets or the like). In the working area 1, a manipulator 4
is arranged; the end of the manipulator arm 5 as well as the
gripping device 6 fastened to the manipulator arm 5 are the only
parts of the manipulator 4 that are illustrated. The manipulator
can be a robot or a similar device that can pivot and rotate the
gripping device and can guide the gripping device along
particularly amovement path. The robot movements are expediently
predetermined such that acceleration forces act on the picked-up
article 3 that can be even a multiple of the acceleration due to
gravity.
In the illustrated embodiment, the working surface 2 is comprised
of longitudinal elements 7 with longitudinal gaps 17 provided
between neighboring longitudinal elements 7. The working surface 2
can thus have the shape of a grid or the like, preferably, the
working surface is formed by a strap belt as illustrated in FIGS. 1
and 7. The strap belt is comprised of individual straps 8 that form
the longitudinal elements 7 and are commonly driven in the
transport direction 9. The articles 3 are transported to the
working area 1 by means of the strap belt 8 comprised of several
straps 8.
The gripping device 6 illustrated in the embodiment has a U-shaped
basic configuration wherein the stay 10 of the U determines the
receiving width u of the gripping device 6. The upper leg 11 of the
U serves as of fastening leg for connecting the gripping device 6
to the manipulator or the manipulator arm 5. The lower leg 12 forms
a gripping finger 13 that can be lowered into the longitudinal gaps
17 between neighboring longitudinal elements 7 of the working
surface 2, i.e., between the straps 8 of the transport belt. In
this way, the support surface 14 of the gripping finger 13 is moved
to the level of the plane of the working surface 2 or it is moved
slightly below this level for which purpose recesses or undercuts
matching the width of the straps 8 are provided in the stay 10. For
picking up the article 3, the gripping device 6 moves forwardly in
the transport direction 9 of the transport belt wherein the forward
movement of the gripping device 6 is faster than the speed of the
transport belt in the transport direction 9. In this way, the
gripping finger 13 moves underneath the article 3, and the article
3 is lifted off the working surface 2 when the gripping device 6 is
moved upwardly. In order to ensure a safe pickup action of the
article 3 by means of the gripping device 6, several gripping
fingers 13 are advantageously provided that extend approximately
parallel and adjacent to one another. In the embodiment according
to FIG. 1, two gripping fingers 13 are arranged that form the
bottom of the gripping device 6. The gripping fingers 13 are
expediently of the same length and engage adjacently positioned
longitudinal gaps of the working surface 2.
The gripping fingers 13 are formed to be longer than the fastening
leg 11 wherein the configuration is selected such that the
connecting area 15 of the fastening leg 11 and the manipulator arm
5 is positioned approximately above the center of gravity of the
gripping device 6. The gripping device 6 itself can be tilted about
a pivot axis 16 that is approximately parallel to the working
surface 2 so that an engagement of the longitudinal gap between two
tightly positioned articles 3 is also possible. The gripping device
6 is moreover rotatable about the vertical axis 18 of the
manipulator arm 5.
According to a preferred embodiment of the invention, the gripping
device 6 is comprised a of components that are arranged rigidly on
the gripping device and are immobile relative to one another. This
means that the U-shaped base member, comprised of one or several
gripping fingers 13, the stay 10 that determined the opening width,
as well as the fastening leg 11, is a rigid configuration without
moveable parts. This has the advantage that during manipulation of
meat articles meat juices or similar liquids cannot flow into gaps
provided for movement of the device. The rigid configuration of the
gripping device ensures highest hygiene requirements; the gripping
device itself can be simply and quickly cleaned.
In order to secure the article 3 within the gripping device 6, the
acceleration forces generated when moving the gripping device to
the target location are used in combination with the force of
gravity. The movement path of the gripping device 6 is
predetermined such that the acceleration forces that are generated
in combination with the force of gravity ensure a safe fixation of
the article in the U-shaped receptacle of the gripping device 6. In
order to be able to utilize also decelerations without losing the
article, it can be advantageous to slightly pivot the gripping
device 6 about the pivot axis 16 so that the contact surface 14 of
the gripping fingers 13 is slightly upwardly angled relative to the
movement direction. Occurring deceleration forces can then be
counteracted by such a slanted position.
Advantageously, the placement of the article 3 is also realized by
a corresponding acceleration of the gripping device in the
direction of the acceleration due to gravity. When the gripping
device acceleration is slightly greater than the acceleration due
to gravity, the article will slightly hover as a result of its
inertia above the support surface 14 of the gripping fingers 13 so
that the article 3 is released from the gripping device 6 by a
prompt retraction of the gripping device from the article 3 and
drops under the effect of the force of gravity onto a target
surface. In this connection, the final position of the article 3
relative to the initial rotational orientation can be changed as
desired. Also, flipping of the article 3 can be performed with the
device according to the invention. When only a minimal free space
is available, it can be advantageous to accelerate the gripping
device first counter to the acceleration due to gravity in the
upward direction in order to subsequently release the article from
the gripping device surface by means of acceleration reversal in
the direction of the acceleration due to gravity and retraction of
the gripping device so that the article is deposited in this
way.
It can be expedient for a safe fixation of the article 3 in the
receptacle of the gripping device 6 to provide lateral support
flanges 19 by which the lateral surfaces of the gripping device 6
are at least partially closed. The support flange 19 is positioned
preferably at a lateral spacing s to the gripping fingers 13 and/or
at a horizontal spacing h relative to the support surface 14 of the
gripping fingers 13. It can be expedient to configure the support
flanges 19 to be shorter than the gripping fingers 13. Expediently,
the support flange 19 is longer than the leg 11 of the gripping
device 6 forming the fastening flange. In order to securely
manipulate even sensitive articles in a safe way, it can be
expedient to provide an additional holding-down device 21 that, for
example, can move out from the fastening leg 11 against the article
3.
The device illustrated in FIGS. 4 and 5 show a conveyor belt 30
that is a belt band, a link chain or the like. In the illustrated
embodiment, the conveyor belt 30 is designed as a link chain 31
having on the topside 32 facing the articles 3 longitudinal
elements 7 that extend transversely to the transport direction 29
of the conveyor belt 30. In the illustrated embodiment, the
longitudinal elements 7 are transverse stays while in the
embodiment according to FIG. 1 the longitudinal elements 7 are
longitudinal stays. The longitudinal elements 7 in the illustrated
embodiment of FIGS. 4 and 5 are interrupted in their longitudinal
extension so that each longitudinal element 7 has gaps 27. The gaps
27 of neighboring longitudinal elements 7 form longitudinal gaps 17
extending in the transport direction 29 while two adjacently
positioned longitudinal elements 7 delimit a transverse stay 37.
The transverse stay 37 forms a longitudinal gap of the conveyor
belt 30 extending transversely to the transport direction 29.
The articles 3 resting on the longitudinal elements 7 can be picked
up in the embodiment according to FIGS. 4 and 5 by a gripping
device 6 of a manipulator 4 transversely to the transport direction
29 as well as longitudinally to the transport direction 29. The
gripping fingers 13 engage either the longitudinal gaps (transverse
gaps 37) extending transversely to the transport direction 29 or,
when the gripping device 8 is aligned accordingly, the longitudinal
gaps 17 extending in the transport direction 29 that are formed in
the embodiment according to FIGS. 4 and 5 by the gaps 27 in the
longitudinal elements 7 (transverse stays).
For engagement of the gripping device 6 transversely to the
transport direction 29 there is the possibility of carrying out a
movement of the gripping fingers 13 to the level of the transverse
stays 37 adjacent to the conveyor belt 30 so that the articles 3
can be placed at a shorter spacing to one another in the transport
direction 29 onto the conveyor belt 30. The free space required
between the articles 3 on the belt 30 can be minimized.
When the gripping device 6 is lowered to the level of the
longitudinal stays 7, the gripping device 6 enters the gaps
transversely to the transport direction 29 of the conveyor belt 30
and is moved at the same time at the speed of the belt 30 in the
transport direction 29 so that picking up the article 3 from the
belt is possible. Preferably, the gripping fingers 13 engage
adjacently positioned (neighboring) gaps. It can also be
advantageous when the gripping fingers 13 engage only every other
gap.
In the embodiment according to FIGS. 6 and 7, a conveyor belt
according to FIG. 1 is illustrated that is preferably formed as a
strap belt. The individual straps 8 form in the sense of the
invention the longitudinal elements 7 and are positioned with
lateral spacing relative to one another so that between the straps
8 gaps 17 are formed that extend in the transport direction 29 of
the straps 8. Underneath the conveyor belt 30 that is formed of the
straps 8 a lifting device 40 is arranged that is comprised of
adjacently positioned fingers 41 that can pass through the
longitudinal gaps 17 of the conveyor belt 30 in order to lift an
article 3 off the topside 32 of the conveyor belt 30 and place it
onto an intermediate support 42, as illustrated in FIG. 6. The
movement of the lifting device 40 embodied as a fork hand is
realized similar to a circular movement as is illustrated in a
dashed line referenced by reference numeral 43.
The gripping device 6 picks up the intermediately stored article 3
from the intermediate support 42 and places it back onto the
conveyor belt 30 in order to increase the density of articles on
the belt. Such an active transfer device can be integrated into the
conveyor belt 30 in order to optimally utilize the capacity of such
a device.
While specific embodiments of the invention have been shown and
described in detail to illustrate the inventive principles, it will
be understood that the invention may be embodied otherwise without
departing from such principles.
* * * * *